Types of Chronic Myeloproliferative Disorders

Chronic myeloproliferative disease is a proliferative disease caused by hematopoietic stem cell tumors. On the basis of general proliferation, a series of cell proliferations will be more prominent and continue to proliferate. For example, polycythemia vera, chronic myeloid leukemia, etc. are relatively common chronic myeloproliferative diseases, which pose a great threat to the health of patients. There is also essential thrombocythemia, etc.

According to the difference in the main cell series of proliferation, it can be divided into 4 types:

① The condition characterized by red blood cell proliferation is called true polycythemia.

② Chronic myeloid leukemia (CML) is characterized by granulocyte proliferation.

③The disease characterized by megakaryocyte proliferation is called essential thrombocythemia.

④ The disease characterized by the proliferation of fibroblasts is called primary myelofibrosis. The causes of this group of diseases are unknown and are more common in middle-aged and elderly people. CML See leukemia. The following are three other types.

Polycythemia vera is a disease in which the total amount of red blood cells in the body is significantly higher than normal due to unexplained reasons, commonly known as plethora of blood. 30% of patients develop myelofibrosis, which eventually leads to bone marrow failure, and about 10% of patients develop acute leukemia. The disease has a slow onset and due to the increase in circulating red blood cells and blood viscosity, it causes headaches and dizziness, and some may even develop bleeding and thrombosis.

Essential thrombocythemia is less common and is characterized by a marked increase in platelets, accompanied by bleeding or thrombosis. The incidence rate between men and women is 2:1. 8% of patients develop myelofibrosis and 10% of patients develop acute leukemia. The disease starts slowly and the spleen may enlarge.

Primary myelofibrosis is a diffuse fibrous proliferation of the bone marrow with unknown etiology, accompanied by extramedullary hematopoiesis (or myeloid metaplasia), mainly in the spleen, but also in the liver and lymph nodes. It is generally believed that myeloid metaplasia is not a compensatory effect of myelofibrosis, but a manifestation of myeloproliferation.

The disease is characterized by an insidious onset and a course of more than 10 years. There is a progressive and obvious enlargement of the spleen, and sometimes the entire abdomen is occupied by the spleen. Due to extramedullary hematopoiesis, immature red blood cells, immature granulocytes and teardrop-like red blood cells appear in the peripheral blood. The bone marrow is difficult to puncture due to fibrosis, and the bone marrow is often unable to be taken out, which is called "dry extraction". A bone marrow biopsy can confirm the diagnosis.